Slack puller



.Aug. 11, 1931. wIA; HEINRICH SLACK FULLER Filed May '3, 1 26 2 Sheets-Sheet 1 mm I: 3. 1

, WALTER. A; IHEINRICI-I, 01'' s1. LOUIS,

Patented Aug. 11, 1931 ITE-oSTATES. PATENT OFF CE MISSOURI, Assieuonrro w. :u. MATTHEWS oonronn'rlou, or say Louis, MISSOURI, A CORPORATION OF ivrrssounr' stAc'x'PULnEn Application filed May 3,

This invention relates to slack pullers, and with regard'to certain more specific features to a slack puller for wire, cable and similar strands. f i I Among the several objects. of theinv ention may be noted'the provision of" an 1111- proved slack puller which is adapted to take up excessive loose slack quickly, and which is adapted to take up with great force residue slack which remains after excessive slack has been taken up; and the provision of' a device of the class described which isv light in weight yetv exceedingly durable and simplein operation. Other objects willbe ln part obvious and in part pointed out hereinafter. The invention, accordingly comprises the elements and combination of elements, features of construction, and arrangements of parts which will be exemplified in thestructure hereinafter described, and the scope of the application of which will be indicated in the following claims. I

i In the accompanying drawings .inwhich is illustrated one of various possible embodi ments of the invention, i I

Fig. 1 is a left side elevation of the slack puller; 7 III 1.

Fig. 2 is a front elevatlon thereof; I I

Fig. 3 is a longitudinal section taken on line 33 of Fig. 4; I I Fig.14is a longitudinal section taken on line 44 of Fig. 53' 7 i f :Fig. 5 is an enlarged lateral section taken on line 5 -5 of Fig. 2 and shows a split nut in closed position Fig. 6 is a view similar to Fig. 5 an d shows the split nut in open position; I r Fig. 7 is a plan view of an end-plate for a split nut assembly;

Fig. 8 is a plan view of anendplatefor a r h el. i

. Fig.9 is a plan view of another end-plate for said split. nut assembly; and I Fig.10 is a detailed view of a ratcheting device shown alternately to the position thereof shown in Fig. 1.

Similar reference characters indicate corresponding parts throughout 7 the several views of the drawings 1926. Serial No. 106,286.-

1 Referring now more particularly to Fig. 1, there is illustrated-at numeral 1 la channel iron or like frame bent to an arc of one hundred and eighty degrees at. a; section 3 thereof. The section 3 is looatedsub 'stantially midway between the two endsof the-channel 1.' The two ends of saidchannel 1 are bolted to a casting 5. The midsection 3 of the channel 1 has a boss7 riveted thereto for the purpose of carrying a swiveled clevis 9. The clevis 9:is held by means of a conventional nut-and-bolt com.- bination 11 andv carries a coupling pin 13 for purposes of fastening it to cable ends and the-like. I Longitudinally located with respect to the channel 1 provided a take-up or draw screw 15 having a square or like typeof thread cut thereon. Any type of thread of properstrength may be used. The screw 15 passes through the casting: and. the parts associated therewith (to be described) and emerges atthe lowerend of the device. It isprovided at its outside or lower end with a preferably non-swivelin clevis 17, which carries a coupling pin 19 or the purpose of fastening to another end of the cable tov be stretched. The other end of the screw has a cross-head 16 pinned theretowhich slidably engages the grooves of the sidesof the channeled frame 1. The screw l5 ca n not rotate but it may move longitudinally. The casting 5 carries areducing gear and 'asplit nut driven thereby, adaptedto engage and disengage the said screw 15.

Referring now moreparticularly to Figs. 3 and 4, there is shown a sidewardly extending portion; 21 ofthe casting 5, formed integrally therewithp ,The portion 21 is bored out to receive a worm gear 23 and a thrust-bearing 25 therefor. The said .bore ofthe portion 21 is also adapted to receive a cap 27 which, after the worm gear 23 is positioned within. the portion 21, is heldyin place by means of a locking screw 29 (see Fig. 6). The gear 23 is keyed or otherwise fastened to a shaft .31. I This shaft 31 passes outwardly fromv the bearing cap 27 and is there provided with a ratchet wheel 33 fas I tened tightly thereto. Rotatably' borne ona stub end 35 of the shaft 31, and on the end of the cap 27, is a ratchet housing 37 of a crank arm 39. The crank arm 39 is provided with a conventional hand grip 41 (Figs. 1 and 2). Within the housing 37 is pivotedafipawl 43. The pawl-43 is'providedwi'th 'two lugs either one of which may engage the teeth of the ratchet 33. A spring 45 reacts from a point in the housing 37 opposite of the pivot of the pawl, against said pawl at a 'point 'near and above the pivot. This point near and above the pivot is provided with a lug 47 adapted to hold the spring 45 in position on the pawl. It is evident from Figs. 1 and 10 that if the s ring45be initially in" a state of compress1on,"thepawl 43 will tendto be 'over-centere'd either onefway orthe'other, depend iiig upon the initial: lateral curvature manuall'y given to-the'spring 45. This initial curvature-is given to the spring by setting the pawlf in'ei'ther of the driving positions desired,'andfor thispurpose can be reached threugh openings in'the housing 37. It may benoted -thatinf'Fig. 1 the driving position ofthe"pawl43 and ratchet 33 "is clbckwisewhilein 10 it is counter clockwise- "('s'ee thearrows inFi gs. 1 and 10). Byt'he above de'sci'ulfied "meansthe worm gear 23 may be rotated in either direction. and as willbe s'eendater its rotation for driving ii'lider "a stretching load is suchthat the thrust -bearing-25 receives the end thrust. When the device is slacked off from its work the thrust is 'in the opposite direction but no refined bearing isrequired because of the-light load under'such conditions. "A nut 49-preventsthe crank 39 from being inudvertently' endwardly" removed.

Thgear 23'meshes with a worm wheel51 cut orotherwise formed integrally with a base53 of-=a housing 55adapted to rotate withs'aid worm wheel 51. The housing'55 comp'risessaid base portion "53, four spacing and "driving steins 57 screwed *and seated to 'a"s hould'er"in' said porti0n53, and an end=plate59= screwed to the top of said' spacin" stenis' 57. It is evident that the Worm w *eel 51, the-base 53, the spacing stems'57 and the""eiid-plate- 59-"may means a unit when driven from the worm "gear23. The direct-ion of rotation dependsupon the directi'on'fof rotation of the crank 39. The endplate 59is provided witha pair of openings 61 (Figs. 6 "and 8) for purposes hereinafter to be described.

-The housing 55 retains a floating split-nut assembly 163. This assembly 63 comprises an eiid plate 65 'rotatably positioned in' a recess of 'said base'53' (Figs.'3, land 9). 'Just below the said late 59 off-the assembly 55 is provided-another end-plate 67 of'said split nut assembly. The plate ,67 is provided with recesses 69 for purposes hereinafter to be described- (Fig.7).

A pair of shouldered pivot members 71 are pivoted between the plates 65 and 67. These members 71 are the pivots upon which a pair of the split nut jaws 73 are adapted to oscillate. The jaws 73 have an open position which is illustrated in Fig. 6 and a closed position which is illustrated in Fig.

"5. They are internally threaded to lit the screw 15 when in their closed positions.

They also coo emwat portions 75 when in said closed position, whereby 'a predeterminedspacing is provided between the semihousing "55' is'rotated' clockwise (Figs. 5 i

and 6). I

The jaws 73 are manually actuated [to open'and close by means of a pair of studs 79 one eachof'which is's crewed into the upper end of a jaw 73 respectively. These studs 79 pass through the openings '69 of said end-plate 67 through said openings 61 in saidend-plate 59;and through cam'slots 81 located in a camming disc 83 mounted rotatably above said end-plate 59 *of I the housing 55. The disc 83 actually bears rotatably 'o'n projections ofthecast'ing 5"and is held in position bymeans of heads on the shouldered studs 79. This disc 83*is" also provided witha plurality of extensions 85 which serve to provide means for manually turning the disc one way or the other.

Itis evident from Figs. 5 and 6' that the slots 81 are arranged to cam the jaws 73 shut when rotated counter-clockwise (Fig. 5), and to cam them' open when rotated clockwise (Fig. After the jaws are cammed shut, they may be rotated to feed the screw 15 into the casting 5. -The driving actionis positive because the drivingjand spacing stems 57 engage the portions 77 of the jaws 73. Thisresults in the split nut assembly beingboth drivenand held shut. The'more or less triangular openings in the plate 59 permit 01": the requisite relative movement between the assembly 55 andthe assembly .63 (including studs 79) needed before engagement takes place between the stems'57' and the jaws 73 (see Figs. 5 and 6). They also provide for the more or less radial movement of said studs 79.

A thrust bearing 87 is provided for-taking theend thrust exerted on the base 53. The curvature of the wormwheelf'teethwitli the worm threads is enough to prevent the "speed reducing, and nut assembly from slipping in the opposite direction. -There 'is n'ever a heavy compression thrust encountered by the device, insofar as it is only 'adapted for tensile applications of the screw-15.- The-device comprises a tension member in any mechanical system to which it is applied.

In order to open the jaws 7 3 after a cable or the like has been drawn up, it is only necessary to reverse the pawl 43, back off the crank 39 slightly in order to free the jaws of the stems 57, and turn the plate 83 clockwise (Figs. 5 and 6). The next cable to be tautened may then have its ends applied to the clevises. The very loose slack may then be taken up, or the device adjusted to a new gap merely by pushing'the screw 15 through the open split nut. After this is done the nut is closed from the plate 83, the ratchet properly set, and the crank turned in the proper direction to drive the closed nut and to positively hold said nut closed. The quick take-up feature may be used, either to adjust the distance between the clevises to a given gap between wire or cable ends, to quickly take up loose slack, or both.

The device may be unslacked by operation from the crank 39 by reversing the ratchet and the direction of cranking. This action drives the stems 57 against the jaws 7 3 from the opposite sides, thereby holding the jaws shut and unscrewing them.

The purpose of the openings 69 in the plate 67 is to permit inward movement of the screws 79 as the jaws 7 3 therewith are closed. The overall size of the nut assembly is thus decreased. The particular shape of said openings 69 need only be such as to accommodate the screws 79. The particular shape shown inthe drawings has been adopted in practice because the same die which makes the, openings 61 in the disc 59 can be made to out these openings 69.

In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained.

As many changes could be made in carrying out the above constructions without departing'from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

. I claim:

1. A slack puller comprising a frame, a housing joined thereto, a screw passing longitudinally and slidably therethrough, means for preventing rotation of the screw, a split nut associated with the housing adapted to fit said screw when closed, to feed the same into and out of said frame upon rotation of the nut, means for opening and closing said nut and means for driving the same, said driving means tending to hold the nut shut with a force which increases as the force exerted by the slack puller increases.

2. A slack puller comprising a frame, a screw mounted in respect to said frame for means longitudinal movement without rotation, a

split nut mounted rotatablywith respect to said frame and adapted tofit said screw when closed and releasing said screw for longitudinal movement when opened and means for driving said splitnut when the nut is closedon the screw, said means tending to hold the split nut closed, the force of which increases as the load pulled by the slack puller increases. 3

3. A slack puller comprising a frame, a housing joined'thereto, a screw passing longitudinallyiandslidably through the housing, means for preventing rotation, of, the screw, a split nut mounted within the housing having swingable jaws for engaging said screw, manual means for openingyand' clos ing said jaws'in respect'to the screw and for holding the same shut with a force which is a function of the driving force of the slack puller.

4:. In a slack puller comprising a longitudinally movable but non-rotatable screw, a split nut comprising jaws pivoted to a floating member, said jaws being engageable with said screw, a rotatable housing surrounding said floating member and adapted to be driven to rotate, manual operable means for moving said jaws to open and closed positions and means associated with said rotatable housing for engaging said jaws, the engagement being such as to effect rotation of the floating member and jaws and to tend to hold said jaws shut.

5. In a slack puller comprising a longitudinally movable but non-rotatable screw, a split nut comprising jaws pivoted to a floating member, said jaws being engageable with said screw, a rotatable housing surrounding said floating member and adapted to be driven to rotate, manual operable means for moving said jaws to open and closed positions and means associated with said rotatable housing for engaging said jaws, the engagement being such as to effect rotation of the floating member and jaws and to tend to hold said jaws shut, and anvils associated with the jaws for limiting their movement upon closure, whereby a predetermined spacing is provided between the jaws and said screw.

6. In a slack puller comprisin a longitudinally movable but non-rotatable screw. a split nut comprising pivot members, jaws separately pivoted to said members, said jaws being in engagement withsaid screw, a rotatable housing surrounding said jaws and adapted to be driven to rotate, means associated with said rotatable housing for engaging said jaws, the engagement being I such as to effect rotation of the jaws and to tend to hold said jaws shut.

7 In a slack puller comprising a longitudinally movable but non-rotatable screw, a split nut comprising pivot members, jaws separately pivoted to said members, said jaws being engageable with said screw, a rotatable housing surrounding said aws and adapted to be driven to rotate, means associated with said rotatable housing for engaging said jaws, camming means on the jaws at the points of engagement, the can gagement being such as to effect rotation of the jaws and to tend to hold said aws shut 'lC and means on the jaws adapted to be en gaged by the engaging means upon reverse rotation, whereby said rotational and hold ing tendency on the jaws may be effected in either direction of rotation.

In testimony whereof, I havesigned my name to this specifioation'this 30th day of April, 1926.

WALTER A. HEINRICH. 

